This is the 494th most frequent Romanian word.
președintelui
"Președintelui" means "of the president" in English.
Here, 'președintelui' is in the genitive case and indicates possession or association, referring to the president of Romania.
Decretul a fost semnat de către președintelui României.
The decree was signed by the president of Romania.
In this sentence, 'președintelui' is used in the genitive case to show possession, describing that the opinions belong to the president.
Am citit un articol despre opiniile președintelui în privința politicilor economice.
I read an article about the president's opinions on economic policies.
Here, 'președintelui' again is used in the genitive case to describe to whom the official message belongs, which is the president.